[Linux-parport] ASYNC I/O Reason: Reverse transfers are _slow_

malcolm blaney mblaney at gmail.com
Thu Jan 28 06:30:44 EST 2010


Hi Johann,

Hopefully this will be of use to you:
http://lists.infradead.org/pipermail/linux-parport/2007-October/000614.html

Malcolm.

2010/1/28 Johann Klammer <klammerr at aon.at>:
> Dirk Jagdmann wrote:
>>
>> Hallo Johann,
>>
>> in what mode did you hook up and talk to the microcontroller? EPP and
>
> It uses ECP protocol using ppdev read() and write() operations in ECP mode.
> The primary hassle seem to be the lack of DMA support for reads.
>>
>> ECP modes should provide adequate performance, but if you "invent"
>> your own protocol, or trigger every byte/nibble with your own function
>> calls to set the parallel port lines, it will always be slow.
>>
>
> _______________________________________________
> Linux-parport mailing list
> Linux-parport at lists.infradead.org
> http://lists.infradead.org/mailman/listinfo/linux-parport
>



More information about the Linux-parport mailing list